By Kirstin Junker, ARC-OVI
On 1 April 2021, Deon was awarded the degree of PhD in Zoology from Stellenbosch University (SU). The Collections Team at the ARC-Onderstepoort Veterinary Institute would like to take this opportunity to congratulate him with this great achievement.
As part of his PhD studies, conducted under the supervision of Prof Conrad Matthee (SU) and Prof Ben Mans (ARC-OVI), Deon elucidated the evolutionary history among species of the ixodid tick genus Rhipicephalus, with special reference to ancestral geographic movements, host-use patterns and climate niches, all of which played various roles in driving the diversification of the genus. Effects of selection pressure on different life stages were determined from shape data for tick mouthparts from specimens housed in the Gertrud Theiler Tick Museum (ARC-OVI), of which Deon has been the Curator since he joined the ARC-OVI in 2016. The obtained data suggest that factors such as host skin thickness, predation/grooming and dehydration off-host play a role in modulating evolutionary responses of Rhipicephalus developmental systems. Additionally, while compiling and studying the relevant tick species, a new Afrotropical tick species, Rhipicephalus afranicus, which had previously been confounded with a Eurasian species, was uncovered from museum collections of African ticks. The detection and description of this new species was possible thanks to an integrative taxonomic approach, based on DNA sequencing and shape analysis of diagnostic morphological features from specimens housed in the Gertrud Theiler Tick Museum.
Deon is no newcomer to the discipline of taxonomy/systematics, and previously studied the biodiversity and evolutionary history of Afrotropical silky lacewings (Neuroptera, Psychopsidae) for his Masters’ degree, under guidance of Prof Catherine Sole and Prof Mervyn Mansell at the University of Pretoria, Department of Zoology & Entomology. With a solid foundation of morphological taxonomy combined with the latest molecular techniques, Deon brings a fresh and innovative approach to the taxa he studies and is a great asset to our Collections. Over the past 4 years, Deon has published 14 papers on the taxonomy, evolution and systematics of lacewings and ticks, with another five pending publication.
Once again, Congratulations, Deon! And great having you on board!